Karissa says that to represent the expression - 7 - (- 9) on number line, she should start at 7 and move units to the IN correct? Explain why or why not.

At a pizza shop 70% of the customers order a pizza 25% of the customers order a salad and 15% of the customers order both a pizza and a salad if s customer is chosen at random what is the probability that he or she orders either a pizza or a salad